This is cross-platform.
” Security researchers have proposed several methods for users to protect their computers from ongoing attacks that target a new and yet-to-be-patched vulnerability in all versions of Java Runtime Environment 7.
…
“The new vulnerability is considered extremely critical and can be exploited to execute malicious code on a system by simply visiting a maliciously crafted Web page from a Web browser that has the Java plug-in enabled… “
Source: PCWorld Business Center
More Six Ways to Protect Against the New Actively Exploited Java Vulnerability